Auxiliary transmission

ABSTRACT

An auxiliary transmission for transmission of power to or from a main transmission to increase the overall speed range of the power gear train in a vehicle.

United States Patent C rooks July 4, 1972 [54] AUXILIARY TRANSMISSION[72] Inventor: James W. Crooks, Milwaukee, Wis.

1,921,598 8/1933 Anderson ..74/681X 3,533,307 10/1970 Gunderson "74/740Primary ExaminerCarlton R. Croyle Assistant ExaminerThomas C. PerryAttarney Arthur L. Nelson Kenneth C. McKivett and Robert B. Benson 57ABSTRACT An auxiliary transmission for transmission of power to or froma main transmission to increase the overall speed range of the [73]Assignee: Allis-Chalmers Manufacturing Company,

Milwaukee, Wis.

[22] Filed: Sept. 3, I970 [211 Appl. No.: 69,260

[52] U.S.Cl ..74/681, 74/740 ..Fl6h 37/08 [58] FieldofSearch ..74/740,681,781

[56] References Cited UNITED STATES PATENTS 1,648,969 11/1927 Steuart .t"74/ 681,

power gear train in a vehicle.

10 Claims, 5 Drawing Figures ri go P'ATENTEDJUH I972 SHEET 1 W 3AUXILIARY TRANSMISSION This invention relates to a transmission and moreparticularly to an auxiliary transmission used in conjunction with amain transmission to increase the speed and torque range of the vehiclepower train.

The conventional power train on a vehicle provides a plurality speedratio which in turn provides desired torque needed to pull the draftload on the vehicle such as a tractor. The power train may also providea higher speed ratio such as the road gear and a reverse to provide thedesired speed and maneuverability for the tractor.

Most modern tractors also include a quick shift ahead of the maintransmission to increase the speed ratios of the power train. Thesequick shift auxiliary transmissions are usually of the two speedarrangement and extend the speed coverage of the main transmission onthe low end of the speed range or on the high end of the speed range butnot both. A more versatile arrangement would provide extension of thespeed range both above and below the main transmission speed range.Accordingly this invention auxiliary transmission which operates both asan overdrive and an underdrive and also a direct drive through the maintransmission, so it doubly extends the overall power train coverage.

This is accomplished by means of a gearing arrangement and therefore noextra controls, clutches, or gears are required than normally would-berequired for a single extension coverage mechanism. The auxiliarytransmission illustrated shows a 3-speed unit but these same principalswould apply to a 2-speed unit, which can be built from the 3-speedarrangement by leaving out the low speed range.

Accordingly it is an objectof this invention to provide a two or a threespeed auxiliary transmission to extend the speed range of the mainvehicle transmission.

It is another object of this invention to provide an auxiliarytransmission which extends the speed coverage of the main transmissionsby extending the speed on the low and the high speed end of thetransmission.

It is a further object of this invention to provide an auxiliarytransmission extending the speed range of the main transmission throughan overdrive and direct drive and an underdrive to extend the overallspeed range of the vehicle power gear train.

It is a further object of this invention to provide an auxiliarytransmission driving through a multiple speed transmission and providingin the lower speedranges of the main transmission a direct drive and twounderdrives while providing in the high speed range of the maintransmission an underdrive, a direct drive, and an overdrive to therebyincrease the speed range coverage of the power gear train of thevehicle.

The objects of this invention are accomplished by providing a planetarygear set in which the input drive is to the ring gear. The planetarygear drives directly through the main transmission or drives through acounter shaft gearset which drives around the main transmission. Theselected power path through the main transmission or the countershaftgearset is controlled by the plurality of clutches and a brake. Theclutching provides for locking of the planetary gearset and a directdrive through the main transmission or a combination drive through themain transmission or a combination drive through the main transmissionand the countershaft gearset. Locking the sun gear to ground provides adrive from the planetary carrier through the main transmission. Thisarrangement provides a 3-speed unit but the same principal would applyfor use of a 2-speed unit by leaving out the low range in which thebrake locks the sun gear to ground or in other brakes the sun gear tothe housing member. The main transmission as illustrated is a 4-speedtransmission through which the auxiliary transmission operates andessentially provides 3- speed extension in each of the 4-speeds for anoverall 12- speed power train for the vehicle.

The preferred embodiments of this invention are illustrated in theattached drawings.

FIG. 1 illustrates the cross-section of the preferred embodiment of thisinvention.

FIG. 2 illustrates a cross section view taken on line II-II of FIG. 1.

FIG. 3 illustratesschematically the preferred embodiment as shown inFIG. 1.

FIG. 4 illustrates a schematic view of one of the embodiments of thisinvention.

FIG. 5 illustrates the gear ran'os of the main and auxiliarytransmissions.

While the main embodiments of this invention are shown in FIGS. 1through 5, it is understood that these embodiments show a 3-speedauxiliary transmission for use in conjunction with the maintransmission.

It is understood that while the preferred embodiments of this inventionare shown in FIG. 1 through 5 that a 2-speed auxiliary transmissioncould be constructed by eliminating the braking feature of the auxiliarytransmission shown. This would provide a 2-speed auxiliary transmissionbut would still provide the overdrive, direct drive and underdrivefeatures of the auxiliary transmission for use in conjunction with themain transmission to extend the power train speed range coverage.

Referring to FIG. 1 the transmission housing 1 supports the ball bearingassembly 2 which rotatably supports the input shaft 3. The input shaft 3forms an. integral radial flange 4 forming a spline 5 on its externalperiphery which receives the mating spline 6 of the ring gear 7. Thering gear 7 also has a spline 8 on its external periphery which receivesa plurality of clutch disks 9. The'drive shaft 10 is rotatably mountedon the bearing assembly 11 androtates concentrically with the inputshaft 3. The drive shaft 10 also forms a spline 160 which engages amating spline 12 on the inner periphery on the planetary carrier 13. Theplanetary carrier 13 is retained in position by the snap ring 14.

Planetary carrier 13 carries a plurality of planet gears 15 which arecarried on a shaft 16 supporting a bushing 17 rotatably mounting eachplanet 15. The shaft 16 also carries the spacers 18 and 19 on the end ofeach of the planet gears 15. The quill shaft 20 rotates on the rollerbearing assemblies 21 and 22 which embrace the drive shaft 10.

The sleeve 26 and pinion gear 27 are formed integral and rotatably mounton the bearing assemblies 28 and 29. The bearing assemblies 28 and 29embrace the quill shaft 20 and provide a freely rotatable support forthe sleeve 26 and pinion gear 27. The clutch hub 30 is retained by thesnap ring 31 on the sleeve 26. The clutch hub 30forrns a spline 32 onits external periphery which receives the clutch disks 33.

The quill shaft 20 forms passages 34 leading to the clutch 35 andpassage 36 leading to the clutch 37. The collar 38 also defines thepassages 39 and 40 which are in communication with the passages 36 and34 respectively. The collar 38 is sealed with the housing by the seal41, 42 and 43 and is sealed with the quill shaft by the seals 44, 45 and46. The passages 39 and 40 in housing 1 are also connected to theconduits 47 and 48 respectively. Conduits 47 and 48 are connectedthrough the valve 49 to the pump 50 to selectively actuate the clutches35 and 37.

The housing 1 supports the bearing assembly 51 which in turn rotatablysupports the inner end of the drive shaft 10 which is integrally withthe drive gear 52. The drive gear 52 drives the gear 53 which will bedescribed subsequently. As shown in FIG. 1 a clutch collar 54 isoperated by a clutch lever 55 to selectively engage the collar 54 withthe synchronizing rings 56 and 57. The clutch teeth 58 and 59 areselectively engaged by the collar 54 to drive the output shaft 60 orgear 69. Clutch collar 54 has a splined surface 61 which engages thesplined surface 62 of the clutch sleeve 63. Clutch sleeve 63 also has aninternal spline 64 which engages the external spline 65 to the outputshaft 60. The bearing assembly 66 is received within the recess 67 inthe drive shaft 10 arid engages the annular facing 68 on the outputshafi 60.

The gear 69 engages the gear 70. The clutch sleeve 63 is retained inposition by the snap ring 71 while the gear 69 is retained in positionby the snap ring 72.

The countershaft gear set 73 includes the gear 74 having a spline 75engaging the spline 76 of the countershaft 77. The

countershaft 77 is rotatably mounted in the bearing assemblies 78 and79. The spacer 80 is positioned between the bearing assembly 79 and thegear 74 while the spacer 81 is positioned between the gear 74 and thebearing 78 and the snap ring 82 maintains the bearings and gear inplace.

The bearing support 83 is integral with the collar 38. The countershaft84 is also supported on the transmission housing 1 and forms a spline 85which engages the internal spline 86 of gear 87. The gear 87 is retainedin position on the countershaft 84 by the snap rings 88 and 89. Gear 87meshes with the gear 90. The countershaft sleeve 150 is splined on itsinternal periphery at 91 and 92 and engages mating splines 93 and 94 ofthe countershafts 77 and 84 respectively.

The drive through the countershaft gear set 73 is initially transmittedthrough the clutch 37. The planetary gear set 95 is locked by actuationof the clutch 35. Brake 96 locks the sun gear 25 to the housing.

The clutch 35 includes the clutch disks 9 on the ring gear 8 and theclutch disks 97 on the clutch annulus 98 which is integral with thequill shaft 20. The piston 99 is received in the cylinder 100 and formsthe fluid pressurizing chamber 101 in communication with the passage 34.The reaction plate 102 is retained within the clutch annulus 98 by theretainer ring 103. Actuation of clutch 35 engages the disks to lock thering gear 7 with the sun gear 95.

Clutch 37 includes clutch disks 33 on the spline portion of the clutchhub 30 which engage the clutch disks 104 on the clutch annulus 98. Thereaction plate 105 has an axial flange portion 106 defining the spline107. The reaction plate 105 is also carried on the clutch annulus 98 andretained in position by the snap ring 109. The piston 110 is receivedwithin the cylinder 111 formed by the annulus 98. The piston 110 and thecylinder 111 form the fluid pressurizing chamber 112 in communicationwith the passage 36 in the hydraulic system.

The brake 96 includes the brake disk 113 on the splined portion 107 ofthe axial flange 106 of reaction place 105. The stator brake disks 1 14are received on the spline portion 115. The reaction plate 116 ismaintained in position by the snap ring 117. Actuation of brake 96 locksthe sun gear 25 to the housing 1.

The brake 96 is actuated when piston 137 in cylinder 118 which forms afluid pressurizing chamber 119 is actuated. The chamber 119 is incommunication with the passage means 138 which is connected to theconduit 139 in the hydraulic system.

Referring to FIG. 4 the schematically illustrated auxiliary transmission120 is the same as that shown in FIG. 1. The main transmission 130 isthe same transmission in which a portion 130 is shown in FIG. 1. Thegear 90 is connected to the output shaft 60 as shown in FIG. 4. The gear52 drives through gear 53 which is connected to jackshaft 121. Thejackshaft 121 is connected to the gear 70, gear 122 and gear 123. Gear122 meshes with 124 while gear 123 meshes with gear 125. The clutchcollar 126 selectively engages gear 124 for drive through the jackshaft60, or gear 125 for drive through the jackshaft 60.

The speed ratios shown in FIG. are overall ratios for the auxiliarytransmission 120 and main transmission 130 and are not intended to belimiting but only for the purpose of illustration.

For the purpose of illustration, FIG. 3 is essentially the same as FIG.4, and the numbers of the gears in the main transmission will beindicated by the same numbers. The auxiliary transmission 120, however,is modified to clutch the planetary carrier 13 to the sun gear 25. Theclutch 126 includes the clutch disks 128 which engage the clutch disks129 in response to operation of the hydraulic actuator 131. Althoughschematically illustrated in FIG. 3, the clutch 127 is essentially thesame construction of that of clutch 35 as described in FIG. 1.

The operation in the auxiliary transmission and the main transmissionwill be described in the following paragraphs.

The drive from the input shaft 3 drives through the planetary gearset95. The planetary carrier and the planetary gears freely rotating, thedrive is transmitted through the sun gear 25 to the drive shaft 10.Drive shaft 10 is integral with the gear 52 and power is transmittedeither through the clutch collar 54 when it clutches gear 52 to shaft 60to directly drive through the main transmission 130, or through one ofthe gears 69, 124 and 125 which is selectively clutched. The clutchcollar 54 can be shifted to engage the gear 69. In this position thedriveshaft 10 drives through gear 52, 53 and jackshaft 121 through thegear 70 and gear 69 to the output shaft 60. This is considered the 3rdgear ratio of the main transmission. The clutch collar 126 can beshifted to engage gear 124 with the output shaft 60 and accordingly thedrive then will drive from the driveshaft 10, through gear 52, gear 53,the jackshaft 60, gear 122, gear 124 to the output shaft 60. This isconsidered the second gear ratio.

When the clutch collar is positioned to clutch gear 125 to the outputshaft 60, the transmission is in 1st gear ratio. The power is thentransmitted from the drive shaft 10 through the gear 52, gear 53,jackshaft 121, gear 123, 125 to the output shaft 60.

When clutch 35, 37 and brake 96 are disengaged, the transmission drivesthrough the planetary gear set to the main transmission 130.

When the clutch 35 is locked, the sun gear 25 is locked to the ring gear7 and the planetary gearset drives directly through drive shaft 10 andthrough the main transmission 130 in a l to 1 ratio. This is the highgear position for the auxiliary transmission 120. With the auxiliarytransmission in the high range the main transmission can be selectivelyengaged in the 1st, 2nd, 3rd or 4th gear range.

The low gear range for the auxiliary transmission 120 is with the clutch35 and 37 disengaged and the brake 96 engaged. In this position the sungear 25 is locked to the housing causing the ring gear 7 to drivethrough the planetary gears 15 and the planetary carrier 13 to the driveshaft 10 to provide an underdrive. The main transmission can beselectively positioned in any of the gear ranges of lst, 2nd, 3rd and4th similarly as provided in the high range of the auxiliarytransmission.

With the auxiliary transmission 120 operating with the brake 96disengaged and the clutch 35 disengaged and clutch 37 engaged, theauxiliary transmission transmits power through the countershaft gearset73 and the main transmission 130. The reaction torque is transmittedthrough the countershaft gearset 73 while the driving torque istransmitted through the main transmission 130. The reaction torqueproduces a negative rotation of the output gear 90 with relation to thedriving torque transmitted through the main transmission 130.Counterrotation through countershaft gearset 73 to the output gear 90and forward rotation through the main transmission to output shaft 60provides an overdrive when the main transmission is in intermediate gearrange.

Accordingly it can be seen that in the 4th gear range of the maintransmission 130, an overdrive, a direct drive, and the underdrive areprovided through the main and auxiliary transmission. When the maintransmission is positioned in the 1st, 2nd and 3rd gear range, theoverall power train including the auxiliary transmission 120 and themain transmission 130 provide two underdrives and a direct drive for thegear train.

The preferred embodiments of this invention have been illustrated asdescribed.

I claim:

1. A gear train for power transmission comprising a main transmissionincluding a plurality of gears and clutch means mounted in a housingproviding a plurality of gear ratios, a drive shaft, a drive gearconnected to said drive shaft, and an output shaft connected to anoutput shaft gear for selectively transmitting power at the plurality ofgear ratios from said transmission, a countershaft gearset including adriven gear drivingly connected to said output shaft gear of said maintransmission, an auxiliary transmission selectively and alternativelyconnected for driving said drive shaft, said auxiliary transmissionincluding a planetary gearset having elements including a ring gear, asun gear, and a plurality of planetary gears supported on a planetarycarrier, an input shaft connected to said ring gear, said drive shaftconnected to said planetary carrier and said drive shaft gear, a firstclutch connected to said sun gear, a friction element of said clutchconnected to at least one of said elements including said ring gear andsaid planetary carrier to selectively lock said planetary gearset, acountershaft drive gear for driving said countershaft gearset, a secondclutch connected between said sun gear and said countershaft drive gearfor selectively driving said countershaft gearset from said sun gear,means selectively and alternatively disengaging and engaging saidclutches of said auxiliary transmission to increase the speed range ofsaid main transmission when operated in conjunction with said auxiliarytransmissions.

2. A gear train for power transmission as set forth in claim 1 includinga brake on said housing having a friction element connected to said sungear for braking said sun gear to the housing.

3. A gear train for power transmission as set forth in claim 1 whereinsaid first clutch includes a friction element connected to saidplanetary carrier to thereby lock to said planetary gearset to providedirect drive from said input shaft to said drive shaft.

4. A'gear train for power transmission as set forth in claim 1 whereinsaid first clutch includes a friction element connected to said ringgear to thereby lock to said planetary gearset to provide direct drivefrom said input shaft to said drive shaft.

5. A gear train for power transmission as set forth in claim 1 whereinsaid second clutch includes a friction element connected to saidcountershaft drive gear providing a power path for reaction torque fromsaid sun gear through said countershaft gearset to said output shaft forreaction torque and a power path for driving torque from said planetarycarrier through said drive shaft and said main transmission to saidoutput shaft.

6. A power train for use in a vehicle as set forth in claim 1 whereinsaid first clutch includes a friction element on said planetary carrierfor locking said sun gear with said planetary carrier and said secondclutch includes a friction element on said countershaft drive gear forconnecting said sun gear with said countershaft gearset to therebyprovide a reaction torque through said countershaft gearset to saidoutput shaft and a driving torque through said main transmission.

7. A gear train for power transmission as set forth in claim 1 whereinsaid first clutch includes a friction element clutching said ring rearto said sun gear to lock said planetary gearset, said second clutchincludes a friction element on said countershaft drive gear connectingsaid sun gear to said countershaft gearset to thereby provide reactiontorque through said countershaft gearset and driving torque through saiddrive shaft in said main transmission to thereby provide an overdrivefrom said input shaft to said output shaft.

8. A gear train for power transmission as set forth in claim 1 includingmeans for selectively engaging a high speed range in said maintransmission, said second clutch includes a friction element on saidcountershaft drive gear providing power transmission from said sun gearto said countershaft gearset to thereby provide a reaction torquethrough said countershaft gearset to said output shaft, and saidplanetaryicarrier drives through said drive shaft to said maintransmission to thereby provide overdrive from said input shaft to saidoutput shaft.

9. A power train for use in a vehicle as set forth in claim 1 includingmeans for selectively engaging a low speed range in said maintransmission, a brake on said housing including a friction elementconnecting said sun gear with said housing to drive from said planetarycarrier through said drive shaft and said main transmission to therebyprovide an underdrive from said input shaft to said output shaft.

10. A power train for use in a vehicle as set forth in claim 1 whereinsaid first clutch includes a friction element on said ring gear forlocking said planetary gearset to provide direct drive from said inputshaft to said drive shaft.

1. A gear train for power transmission comprising a main transmissionincluding a plurality of gears and clutch means mounted in a housingproviding a plurality of gear ratios, a drive shaft, a drive gearconnected to said drive shaft, and an output shaft connected to anoutput shaft gear for selectively transmitting power at the plurality ofgear ratios from said transmission, a countershaft gearset including adriven gear drivingly connected to said output shaft gear of said maintransmission, an auxiliary transmission selectively and alternativelyconnected for driving said drive shaft, said auxiliary transmissionincluding a planetary gearset having elements including a ring gear, asun gear, and a plurality of planetary gears supported on a planetarycarrier, an input shaft connected to said ring gear, said drive shaftconnected to said planetary carrier and said drive shaft gear, a firstclutch connected to said sun gear, a friction element of said clutchconnected to at least one of said elements including said ring gear andsaid planetary carrier to selectively lock said planetary gearset, acountershaft drive gear for driving said countershaft gearset, a secondclutch connected between said sun gear and said countershaft drive gearfor selectively driving said countershaft gearset from said sun gear,means selectively and alternatively disengaging and engaging saidclutches of said auxiliary transmission to increase the speed range ofsaid main transmission when operated in conjunction with said auxiliarytransmissions.
 2. A gear train for power transmission as set forth inclaim 1 including a brake on said housing having a friction elementconnected to said sun gear for braking said sun gear to the housing. 3.A gear train for power transmission as set forth in claim 1 wherein saidfirst clutch includes a friction element connected to said planetarycarrier to thereby lock to said planetary gearset to provide directdrive from said input shaft to said drive shaft.
 4. A gear train forpower transmission as set forth in claim 1 wherein said first clutchincludes a friction element connected to said ring gear to thereby lockto said planetary gearset to provide direct drive from said input shaftto said drive shaft.
 5. A gear train for power transmission as set forthin claim 1 wherein said second clutch includes a friction elementconnected to said countershaft drive gear providing a power path forreaction torque from said sun gear through said countershaft gearset tosaid output shaft for reaction torque and a power path for drivingtorque from said planetary carrier through said drive shaft and saidmain transmission to said output shaft.
 6. A power train for use in avehicle as set forth in claim 1 wherein said first clutch includes afriction element on said planetary carrier for locking said sun gearwith said planetary carrier and said second clutch includes a frictionelement on said countershaft drive gear for connecting said sun gearwith said countershaft gearset to thereby provide a reaction torquethrough said countershaft gearset to said output shaft and a drivingtorque throUgh said main transmission.
 7. A gear train for powertransmission as set forth in claim 1 wherein said first clutch includesa friction element clutching said ring rear to said sun gear to locksaid planetary gearset, said second clutch includes a friction elementon said countershaft drive gear connecting said sun gear to saidcountershaft gearset to thereby provide reaction torque through saidcountershaft gearset and driving torque through said drive shaft in saidmain transmission to thereby provide an overdrive from said input shaftto said output shaft.
 8. A gear train for power transmission as setforth in claim 1 including means for selectively engaging a high speedrange in said main transmission, said second clutch includes a frictionelement on said countershaft drive gear providing power transmissionfrom said sun gear to said countershaft gearset to thereby provide areaction torque through said countershaft gearset to said output shaft,and said planetary carrier drives through said drive shaft to said maintransmission to thereby provide overdrive from said input shaft to saidoutput shaft.
 9. A power train for use in a vehicle as set forth inclaim 1 including means for selectively engaging a low speed range insaid main transmission, a brake on said housing including a frictionelement connecting said sun gear with said housing to drive from saidplanetary carrier through said drive shaft and said main transmission tothereby provide an underdrive from said input shaft to said outputshaft.
 10. A power train for use in a vehicle as set forth in claim 1wherein said first clutch includes a friction element on said ring gearfor locking said planetary gearset to provide direct drive from saidinput shaft to said drive shaft.